<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
       
        <input type="button" value="点击" v-for="i in n " @click="add">

        <ul>
            <h1 v-for="i in hdlist">
                {{i}}
            </h1>
        </ul>
        <button @click.once="addbtn">点我增加一行</button>


    </div>

    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>


    <script>
     var app = new Vue({
     el:"#app",
     data:{
        
        hdlist:[],
        n:1
     },
     methods:{
      
        add: function () {
          this.n++
        },
        addbtn(){
                    this.hdlist.push("我是新增的一行")
                }
     }

    })
      


    </script>
</body>
</html> 
 
